I built it and tried it out a bit with Godot on Linux. It seems OK (the UI is a bit on the "- how many widgets do you want? - yes" side), but also a bit janky. Trying to change the font for the editor didn't work, hovering over a variable to see its value either does nothing (but there is a sub-second cursor change that indicates something is supposed to happen) or it shows an error from GDB about trying to use an expression with a type or keyword (so there was an intent to show a value on a tooltip, it is just broken) - doubleclicking on a variable does add it in some panel with its current value and a timestamp, so the functionality for reading values/expressions from the UI is there too, just not done in the same way as the tooltips.
If polished a bit it could be useful, though from all the frontends i've tried the one i disliked the least (none are great) is Gede[0] (which i just noticed had a new release a few hours ago) as it has a very simple and straightforward UI and while it doesn't expose much functionality, what exposes seem to work fine without bugs.
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